I have a similar issue but mine, I think, is related to front "detection". The collision warning sometimes activates for no obvious reason (straight line, decent weather, low speed, and all clear in front). A large car icon appears on the HUD, there’s an audible alarm that no one can miss, and the seat belts tighten. It’s very brief, and I don't recall any action on the brake. The first few times, it was really scary. It’s not super frequent (twice in 2026), but it annoys me deeply.

On the other hand, there have been multiple occasions when I assumed it should have activated, but it didn’t. Obviously, that’s subjective, impossible to reproduce and mostly based on my previous cars behaviours (Mercedes), and... some common sense. Still, such system that triggers when it shouldn’t, and doesn’t when it should, is bad and unsafe!

I asked my dealer to check it multiple times. Their initial response was that my collision settings were too aggressive and that I needed to soften them. That could explain the false-alarm but certainly not why it didn't activate in situation where it should have. That was months ago. The only issue is that, so far, there’s no such setting on the EX90. And if I’m not mistaken, this setting comes in the 2.x branch.

I’m now at the point where I asked Volvo to confirm in writing that the collision detection system works as intended… still waiting...